Collapsible last



v. J. LEVAGGI, JR 2,429,233

Oct; 21,1947.

' COLLAPSIBLE LAST Filed May 25, 1946 Patented Oct. 21, 1947 COLLAPSIBLELAST 7 Victor J. Levaggi, Jr., Beverly, Mass, assignor to United LastCompany, Boston, Mass, a corporation of Maine Application May 25, 1946,Serial No. 672,282

Claims. 1

The purpose of the present invention is to provide improved means forconnecting the forepart and the heel part of a two-part collapsible lastof the type in which collapsing movement includes components of angularmovement about a pivot in the forepart and angular movement about anindividual pivot in the heel part. An example of a last in this categoryis illustrated in my United States Letters Patent No. 2,404,805, grantedJuly 30, 1946.

The connecting means illustrated in the patent identified abovepossesses the desirable quality of resilience that enables .it to shiftone of the parts (forepart or heel part) to its collapsed position andto its normal (last-forming) position from an intermediate point betweenthose positions, and to draw the parts one against the other in theirnormal relation. For making the majority of shoes intended for streetwear, especially the smaller and medium sizes, connecting means ofmoderate strength are entirely satisfactory, but for lasts used inmaking large heavy shoes, stronger connecting means are preferred.

To this end, the present invention provides connecting means thatpossesses relatively great strength and last-tightening ability withoutexcessive weight and without requiring excessive weakening of the woodenparts of a last. A fea-- ture of the invention is an inverted togglecomprising a long link anda short link, one connected to the forepart bya pivot pin and the other likewise connected to the heel part by anindividual pin, the short link being nested in a loop of the long linkand on of the links having a knuckle seated in a recess in the other toform a kneejoint without a pin and without lapped portions. The loop ofthe long link is provided with an interior arcuate surface by which thekneeforming portions of the links are confined against radialdisplacement, and when the links are assem'bled in a last they areconfined against axial displacement by the confronting walls of the kerfin which they are situated.

One of the links, preferably the long one, may be made to provide afactor of resilience in a lengthwise direction to render it contractilewhen it is abnormally extended and therefore capable of drawing theforepart and the heel part one against the other. Such contractileeffect is use ful not only to resist movement of the knee-joint acrossits dead-center line but also to close the crack between a forepart anda heel part commonly caused by the buckling stress to which a last issubjected in some shoe machines, for ex ample, sole-leveling machines.

The drawings include a novel jack or stand provided with means fortripping the toggle and cocking it to lock the forepart and heel part ofa last in their normal relation.

Referring to the drawings,

Fig. l is a side elevation of an inverted last embodying the invention,broken lines indicating the position of the forepart when the last iscollapsed;

Fig. 2 is a longitudinal section of the last in which the toggle hasbeen tripped;

Fig. 3 is a longitudinal section in which the last is collapsed;

Fig. 4 is a longitudinal section of the last in which the toggle isabout to be cocked;

Fig. 5 is a sectional view indicated by line V-V in Fig. 4;

Fig. 6 is a perspective view of the links that provide an invertedtoggle; and

Fig. 7 is an elevation, partly in section, of a.

jack or stand for operating the toggle.

The last comprises a forepart Iii and a heel part ii havingcounterpartal jointv surfaces including a ridge 12 extending widthwiseon the heel part, and a Valley 13 in the forepart. When the ridge isnested in the valley it registers the parts In and I I in their normalrelation and is effective also to sustain the buckling stress to whichthe last may be subjected in a sole-leveling machine.

A kerf It extends heightwise in the joint por tion of the forepart andintersects the valley It. A corresponding kerf l5 extends heightwise in;the joint portion of the heel part and intersects the ridge 52. Both ofthese kerfs are occupied by a long link it one end of which is connectedto the forepart by a pivot pin ll. That portion of the link it whichlies in the heel part includes a loop l8, preferably closed, in which ashort link it! is nestered. These links are of equal thickness and aremaintained in flush relation by the confronting parallel walls Zii, 20of the kerf in the heel part which are spaced accordingly. A pivot pin2| connects the short link and the heel part. The links and the pivotpins are so organized as to provide an inverted toggle, that is, atoggle that will draw the parts tightly one against the other when thepivot pins and the knee of the toggle are on their dead-center line ornear the latter as in Fig. 1.

The knee of the toggle is formed in part by 'an outcurved end 22 of theshort link and an interior incurved recess 23 in the loop IS. The end22- constitutes a semi-cylindrical knuckle, and the recess provides asemi-cylindrical bearing surface for the knuckle without requiring anypivot pin in the knee-joint. The loop l8 also provides an interiorarcuate surface 24 by which the short link is constrained to maintainits knuckle seated in the recess 23 without unduly limiting the relativeangular movement of the links. The surface 24 is opposite the recess 23and concentrically related to the center thereof. The space bounded bythe loop l8 provides clearance for ashort range of angular movement ofthe links in one direction from their dead-center position (Fig. 1) toavoid accidental tripping of the toggle, and for a long range ofmovement in the opposite direction from that position to permitcollapsing the last.

The pivot pins H and 21 are so located as to distort the loop 18slightly and thereby stretch the link l6 when the knee of the toggle ison a line intersecting the centers of the pins. The reactionary forcethus set up in the link 16 maintains the abutting surfaces of theforepart and heel part pressed tightly one against the other, and guardsagainst accidental movement of the kneejoint across the pin line in bothdirections. The dead-center line of the toggle intersects the valley l3only when the ridge I2 is nested therein. To provide for contractileaction of the link Hi the latter is made of resilient steel and theportions 25 and 26 of the loop are curved and slender enough to beflexed slightly by the force developed by the toggle. A supplementalcomponent of flexure is afforded by the crooked relation of the loop l8and the offset portion of the link it connecting it and the pin ll, thatportion being offset to one side of the direct line of tension.

To trip the toggle and thereby permit collapsing the last it isnecessary merely to shift the center of the knee-joint across the pinline from the position represented in Fig. 1. That will place the linksin the relation represented in Fig. 2. Once the toggle has been tripped,its knee-joint is left free to swing upwardly about the pivot pin 2| torelease the forepart from the ridge 12 of the heel part. This release,in turn, permits the long link and the iorepart to be shifted to thepositions represented in Fig. 3 in which the position of the iorepartcorresponds to that represented by dotted lines in Fig. 1.

The jack or stand illustrated in Fig. '7 has provisions for tripping andcocking the toggle by swinging the long link about its pivot pin ll. Thebase 30 of the stand may be fastened to a bench with screws (notindicated). The upright portion 3| of the stand has a vertical bore toprovide a step-bearing for a cylindrical spindle 32 to which a collar 33is afiixed, This collar rests on the upper end of the step-bearing.Another collar 34 is fastened to the spindle by a pin 35, and is locatedbelow the bearing to prevent pulling the spindle out of the stand and toprovide a small hole (not shown) to receive one end of a torsion spring36. The other end of the spring is anchored to the stand 3i. The pin 35projects through a segmental slot 3! in the stand to serve as a handleby which the spindle may be turned about its axis through an angle ofabout 60". The spring will normally return the pin 35 to one end of theslot.

.Above the collar 33 one side of the spindle is cut away for clearance.The spindle is thus provided with a semicylindrical portion 38 and anoverhanging lip 39 adapted to be engaged by a trigger 48 formed on thelong link IS. A steel socket or thimble 42 is embedded in the cone ofthe heel part to receive the spindle 32, and is provided with a slot 43through which the trig er 40 may project to be engaged by the upper sideof the lip 39 (Fig. 2) or by the lower side thereof 7 (Fig. 4) as thecase may be.

A last, shod or unshod, may be collapsed as follows: if the toggle iscooked (Fig. 1) the trigger 40 will project into the socket 42 farenough to overlap any arcuate portion of the upper end of the spindle 32that may extend across, or part Way across, the slot 43. The operatormay establish the desired angular relation of the spindle and the lastby turning one or the other before pressing the heel part toward thecollar 33. Once the tip of the trigger is seated on the top of thespindle, it will temporarily arrest the descent of the last, but amoderate downward pressure on the heel part will overcome the resistanceof the toggle and thereby shift the knee of the toggle across the pinline to the position represented in Fig. 2. The last may then becollapsed by shifting the forepart to the position represented in Fig.3, in the course of which the trigger 40 will be retracted fromengagement with the spindle and will consequently enable the heel partto drop to a seat on the collar 33.

To return the parts to their locked relation, with or without placing ashoe on the last, the first step is to place the forepart in itslast-forming position (Fig. 4). This step will thrust the trigger 40into the thimble 42, but at this stage the tip of the trigger will bebelow instead of above the lip 39. If, now, the heel part be liftedwhile the lip 39 overlies the trigger as in Figs. 4 and 5, the centerline of the two pins I1 and 2| will be shifted across the center of thekneejoint of the toggle, and the latter will be thereby cooked to lockthe parts as in Fig, 1. The final angular movement of the link It due tolifting the heel part will retract the tip of the trigger enough toenable it to clear the lip 39 and thereby release the last from thespindle.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link, the long link occupying both of said kerfs andhaving a loop in the heel part, a pivot pin connecting the long link andthe forepart, the short link being nested in said loop, a pivot pinconnecting the short link and the heel part, said loop and one end ofthe short link having semi-cylindrical bearing surfaces forming the kneeof the toggle.

2. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link of equal thickness lying in flush relation, thelong link occupying both of said kerfs and having a loop in which theshort link is nested, a pivot pin connecting the long link and one ofsaid parts, and a pivot pin connecting the short link and the other oneof said parts, said loop and the short link having one a recess and theother a knuckle forming the knee of the toggle.

3. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link of equal thickness, the long link occupying bothof said kerfs and having a loop in which the short link is nested, saidloop and the short link having one a recess and the other a knuckleforming the knee of the toggle, a pivot pin connecting the long link andthe forepart, and a pivot pin connecting the short link and the heelpart, the confronting walls of said kerf in the heel part being spacedto maintain flush relation of the links.

4. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link, the long link occupying both of said kerfs andhaving a resilient closed loop in which the short link is nested, apivot pin connecting the long link and one of said parts, and a pivotpin connecting the short link and the other one Of said parts, said loopand the short link having one a recess and the other a knuckle formingthe knee of the taggle, and said pins being located far enough from thejoint surfaces to stress the links endwise when the knee is on thedead-center line of the pins.

5. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link, the long link occupying both of said kerfs andhaving a loop in the heel part, a pivot pin connecting the long link andthe forepart, the short link being nested in said loop, and a pivot pinconnecting the short link and the heel part, said loop and one end ofthe short link having one a recess and the other a knuckle forming theknee of the taggle, and the space bounded by said loop providingclearance for a short range of angular movement of the links in onedirection from their dead-center position and for a long range of suchmovement in the opposite direction from that position.

6. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, the heel part also having a passagewayextending from its kerf to the top of its cone, an inverted togglecomprising a long link and a short link, the long link occupying both ofsaid kerfs and having a loop in the heel part, a pivot pin connectingthe long link and the forepart, the short link being nested in saidloop, and a pivot pin connecting the short link and the heel part, saidloop and the short link having one a recess and the other a knuckleforming the knee of the toggle, and the rear end of the long link beingaccessible to an instrumentality inserted into said passageway tooperate the toggle.

'7. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link, the long link occupying both of said kerfs andhaving a loop in the heel part, th short link being nested in said loop,the loop and the short link having one a recess and the other a knuckleforming the knee of the toggle, a pivot pin connecting the long link andthe forepart, and a pivot pin connecting the short link and the heelpart, the cone of the heel part having a socket and the rear end of thelong link being movable in said socket to cock and trip the toggle.

8. A two-part collapsible last comprising a forepart and a heel parthaving oblique abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, the joint end of the heel part alsohaving a ridge extending widthwis thereof and the forepart having acounterpartal valley to receive the ridge and thereby register the partsin last-forming relation, an inverted toggle comprising a long link anda short link, the long link occupying both of said kerfs and having aloop in the heel part, the short link being nested in said loop, a pivotpin connecting the long link and the forepart, and a pivot pinconnecting the short link and the heel part, said loop and the shortlink having abutting surfaces forming the knee of the toggle, said linksand said pins being arranged to locate the dead-center line of thetoggle in a plane intersecting said valley when said ridge is nested insaid valley.

9. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link, the long link occupying both of said kerfs andhaving a loop in the heel part, a pivot pin connecting the long link andthe forepart, the short link being nested in said loop, and a pivot pinconnecting the short link and the heel part, said loop and one end ofthe short link having one a recess and the other a knuckle forming theknee of the toggle, and the loop also having an interior arcuate surfacein concentric relation to the axis of said knee and arranged to engagethe other end of the short link to maintain cooperative relation of theknee-forming elements.

10. A two-part collapsible last comprising a forepart and a heel parthaving abutting joint surfaces and each having a kerf extendingheightwise in its joint portion, an inverted toggle comprising a longlink and a short link, the long link occupying both of said kerfs andhaving a closed loop in the heel part, a pivot pin connecting the longlink and the forepart, the short link being nested in said loop andhaving an outcurved end an interior incurved recess in which saidknuckle is seated to form the knee of the toggle, and a pivot pinconnecting the short link and the heel part, said loop also having aninterior arcuate surface opposite said recess and arranged to maintainthe knuckle of the short link in the recess.

VICTOR J. LEVAGGI, JR.

forming a knuckle, said loop having I

